Yesterday’s team announcements may have reinforced confidence among Glasgow Warriors supporters that their heroes will claim the bonus point win tomorrow that will see them close in on a place in the Champions Cup quarter-finals, but their head coach has admitted to feeling uneasy about the prospect of facing sub-strength opposition.

Dave Rennie explained that he fully understood the thinking of Cardiff counterpart John Mulvihill, now that his side is out of the competition, having done the same sort of thing a year ago when his side was out of contention heading into the final batch of matches.

The visitors’ starting XV shows no fewer than a dozen changes to the team that played host to Glasgow in their previous meeting in this competition when both were vying to stay in the competition on its second weekend.

However, Rennie knows, too, that there are risks involved in coming up against a team packed with players looking to make names for themselves and which is something of an unknown quantity.

“I wasn’t sure what they’d bring,” he said of the implications for preparing his team this week.

“I understand, because we did something similar last year when we were out of the mix and took a pretty young side to Leinster and then brought a lot of guys back for Exeter at home. To be honest, it makes me more nervous. What we know is that we can’t under-estimate anyone.

“If we bring the level of physicality and the level of accuracy, can hang onto the ball and create turnovers through line speed in defence then hopefully we can hurt them from there, but obviously there is a handful of boys that we don’t know much about.”

Those key messages should be that much easier to drive home on the back of three successive defeats that must mean there is no possibility of Glasgow suffering from the sort of complacency that might otherwise have been a factor for a side that carries even more of an attacking threat than it did when claiming a bonus point in Cardiff with Stuart Hogg and Sam Johnson having missed that match through injury.

Elsewhere they, too, have issues to deal with, most notably Jonny Gray, omni-present for their big matches in recent years and, arguably more importantly in their current circumstances, his fellow international Pete Horne having been ruled out through injury.

Second row cover is such that they are still able to leave another regular Scotland squad member, Tim Swinson, on their bench, but Horne’s unavailability has exacerbated a play-making problem that has been caused by Adam Hastings’ recent loss of form.

Rennie admitted that Horne had been set to be asked to take over the reins at stand off this weekend before it became clear that the knee injury suffered against Edinburgh a fortnight ago had proven slightly more serious than expected, to the extent that he has undergone a scan.

The midfielder is still expected to be fit in time for the start of the Six Nations Championship in three weeks time, but rather than revert to Hastings, who played in all four of Scotland’s autumn Tests, he has called upon South African Brandon Thompson, who has started just two matches this season, having yet to play in the Champions Cup this season and just once previously.

“It is a big game (for him), but so was the confidence we have in him,” said Rennie.

“I thought he was excellent against Scarlets and very strong against Ospreys when he started and played 80 minutes. He has been training with us for a year and a half and he is clear about what we’re trying to do. It’s exciting for him.”

As well as the dip in form that has affected Hastings’ decision-making, old failings seem to have re-emerged, with opponents getting the better of Glasgow in the combat zones, but Rennie is convinced that his squad has what it takes to impose itself.

“We have not got a result the last few weeks but we have created a lot of opportunities,” he said.

“We go through every game with a fine tooth comb and there were areas where we were really sharp in the first part of the year we have not done that recently. We will keep trying to do what we do but better this weekend.”